【jsqlpaser使用008】 过滤算子

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过滤算子

public class FiltersNodeHandler extends BaseOperatorNodeHandler {
    public FiltersNodeHandler(DdlMutableGraphContext mutableGraph, DdlNode node) {
        super(mutableGraph, node);
    }

    @Override
    public PlainSelect sql() {
        //获取前置节点的sql
        PlainSelect preSql = prePlainSelect();
        DdlNode.FilterNode filterNode = currentNode().getOperators().getFilterNode();
        //最外层的条件
        Boolean logic = filterNode.getLogic();
        //先拼接内层的条件
        List<DdlNode.Children> childrens = filterNode.getChildren();
        if (!CollectionUtils.isEmpty(childrens)) {
            //拼接内层条件子节点
            Expression expressionOut;
            for (DdlNode.Children children : childrens) {
                Expression where = preSql.getWhere();
                //子节点的操作字段
                Boolean logicChild = children.getLogic();
                //遍历第一个子节点
                List<DdlNode.Operand> operands = children.getOperand();
                if (CollectionUtil.isNotEmpty(operands)) {
                    //operand共用同一个子logicChild
                    //不等于1并且为奇数的时候创建
                    int size = operands.size();
                    Expression innerExpression = null;
                    for (int i = 0; i < size; i++) {
                        //为偶数才创建
                        if ((i & 1) == 0) {
                            if (Objects.nonNull(logicChild)) {
                                if (logicChild) {
                                    AndExpressionExtend andExpression = new AndExpressionExtend();
                                    if (innerExpression != null) {
                                        andExpression.setLeftExpression(innerExpression);
                                    }
                                    innerExpression = andExpression;
                                } else {
                                    OrExpressionExtend orExpression = new OrExpressionExtend();
                                    if (innerExpression != null) {
                                        orExpression.setLeftExpression(innerExpression);
                                    }
                                    innerExpression = orExpression;
                                }
                            }
                        }
                        String operator = operands.get(i).getOperator();
                        String name = operands.get(i).getName();
                        String value = operands.get(i).getValue();
                        String type = operands.get(i).getType();
                        Expression temp;
                        Expression expressionRight;
                        IsNullExpression isNullExpression;
                        InExpression inExpression;
                        Between between;
                        ExistsExpression existsExpression;
                        LikeExpression likeExpression;
                        Expression startExpression;
                        Expression endExpression;
                        String[] split;
                        switch (operator) {
                            case "=":
                                EqualsTo equalsTo = new EqualsTo();
                                equalsTo.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                equalsTo.setRightExpression(expressionRight);
                                temp = equalsTo;
                                break;
                            case "!=":
                                NotEqualsTo notEqualsTo = new NotEqualsTo();
                                notEqualsTo.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                notEqualsTo.setRightExpression(expressionRight);
                                temp = notEqualsTo;
                                break;
                            case "in":
                                inExpression = new InExpression();
                                inExpression.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                inExpression.setRightExpression(expressionRight);
                                temp = inExpression;
                                break;
                            case "not in":
                                inExpression = new InExpression();
                                inExpression.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                inExpression.setRightExpression(expressionRight);
                                inExpression.setNot(true);
                                temp = inExpression;
                                break;
                            case "is null":
                                isNullExpression = new IsNullExpression();
                                isNullExpression.setLeftExpression(new Column(name));
                                temp = isNullExpression;
                                break;
                            case "is not null":
                                isNullExpression = new IsNullExpression();
                                isNullExpression.setLeftExpression(new Column(name));
                                isNullExpression.setNot(true);
                                temp = isNullExpression;
                                break;
                            case "like":
                                likeExpression = new LikeExpression();
                                likeExpression.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                likeExpression.setRightExpression(expressionRight);
                                temp = likeExpression;
                                break;
                            case "not like":
                                likeExpression = new LikeExpression();
                                likeExpression.setNot(true);
                                likeExpression.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                likeExpression.setRightExpression(expressionRight);
                                temp = likeExpression;
                                break;
                            case ">":
                                GreaterThan greaterThan = new GreaterThan();
                                greaterThan.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                greaterThan.setRightExpression(expressionRight);
                                temp = greaterThan;
                                break;
                            case ">=":
                                GreaterThanEquals greaterThanEquals = new GreaterThanEquals();
                                greaterThanEquals.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                greaterThanEquals.setRightExpression(expressionRight);
                                temp = greaterThanEquals;
                                break;
                            case "<":
                                MinorThan minorThan = new MinorThan();
                                minorThan.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                minorThan.setRightExpression(expressionRight);
                                temp = minorThan;
                                break;
                            case "<=":
                                MinorThanEquals minorThanEquals = new MinorThanEquals();
                                minorThanEquals.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                minorThanEquals.setRightExpression(expressionRight);
                                temp = minorThanEquals;
                                break;
                            case "between":
                                between = new Between();
                                between.setLeftExpression(new Column(name));
                                split = value.split(",");
                                startExpression = this.getRightExpression(split[0], type);
                                endExpression = this.getRightExpression(split[1], type);
                                between.setBetweenExpressionStart(startExpression);
                                between.setBetweenExpressionEnd(endExpression);
                                temp = between;
                                break;
                            case "not between":
                                between = new Between();
                                between.setLeftExpression(new Column(name));
                                split = value.split(",");
                                startExpression = this.getRightExpression(split[0], type);
                                endExpression = this.getRightExpression(split[1], type);
                                between.setBetweenExpressionStart(startExpression);
                                between.setBetweenExpressionEnd(endExpression);
                                between.setNot(true);
                                temp = between;
                                break;
                            case "exists":
                                existsExpression = new ExistsExpression();
                                expressionRight = this.getRightExpression(value, type);
                                existsExpression.setRightExpression(expressionRight);
                                temp = existsExpression;
                                break;
                            case "not exists":
                                existsExpression = new ExistsExpression();
                                expressionRight = this.getRightExpression(value, type);
                                existsExpression.setRightExpression(expressionRight);
                                existsExpression.setNot(true);
                                temp = existsExpression;
                                break;
                            case "contains":
                                Matches matches = new Matches();
                                matches.setLeftExpression(new Column(name));
                                expressionRight = this.getRightExpression(value, type);
                                matches.setRightExpression(expressionRight);
                                temp = matches;
                                break;
                            default:
                                throw new DdlException("操作符不存在");
                        }
                        if (Objects.nonNull(logicChild)) {
                            if (logicChild) {
                                AndExpressionExtend andExpression = (AndExpressionExtend) innerExpression;
                                if (andExpression.getLeftExpression() == null) {
                                    andExpression.setLeftExpression(temp);
                                } else {
                                    andExpression.setRightExpression(temp);
                                }
                                innerExpression = andExpression;
                            } else {
                                OrExpressionExtend orExpression = (OrExpressionExtend) innerExpression;
                                if (orExpression.getLeftExpression() == null) {
                                    orExpression.setLeftExpression(temp);
                                } else {
                                    orExpression.setRightExpression(temp);
                                }
                                orExpression.setLeftExpression(temp);
                                innerExpression = orExpression;
                            }
                        } else {
                            innerExpression = temp;
                        }
                        if (i == size - 1) {
                            //拼接外层的条件
                            expressionOut = innerExpression;
                            if (Objects.nonNull(where)) {
                                if (!logic) {
                                    expressionOut = new OrExpressionExtend(where, expressionOut);
                                } else {
                                    expressionOut = new AndExpressionExtend(where, expressionOut);
                                }
                            }
                            preSql.setWhere(expressionOut);
                        }
                    }
                }
            }
        }
        log(preSql.toString());
        return preSql;
    }

    /**
     * 获取右端表达式
     */
    private Expression getRightExpression(String value, String type) {
        //默认是String类型
        Expression expression = new StringValue(value);
        if (DataTypeEnum.STRING.toString().equals(type)) {
            expression = new StringValue(value);
        }
        if (DataTypeEnum.UINT_8.toString().equals(type) || DataTypeEnum.UINT32.toString().equals(type)) {
            expression = new LongValue(value);
        }
        if (DataTypeEnum.DATE.toString().equals(type)) {
            expression = new DateValue(value);
        }
        if (DataTypeEnum.TIME.toString().equals(type)) {
            expression = new TimeValue(value);
        }
        if (DataTypeEnum.DOUBLE.toString().equals(type)) {
            expression = new DoubleValue(value);
        }
        if (DataTypeEnum.HEX.toString().equals(type)) {
            expression = new HexValue(value);
        }
        if (DataTypeEnum.NULL.toString().equals(type)) {
            expression = new NullValue();
        }
        return expression;
    }

    @Override
    public List<DdlColumn> columns() {
        super.checkNode();
        return super.preColumns();
    }
}

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